Gas turbines, also called combustion turbines, are used to power aircraft, trains, ships, tanks, and generators. Such turbines have a rotating compressor coupled upstream from a turbine. A combustion chamber, or combustor, is positioned between the compressor and the turbine. Energy is added to a gas stream passing through the combustor, in which fuel is mixed with air and ignited.
Combustion of the fuel increases the temperature within the combustor. Often, combustor designers design combustors, including the materials used to form portions of the combustors, to withstand a specific increase in temperature to a maximum temperature. Further, combustor designers often design combustors with a specific maximum temperature in mind, which is typically limited by the material capability.
One problem found in conventional combustors is that the mere operation of the combustors causes thermal degradation of the components. Further, any upward deviations to the maximum temperature may cause accelerated thermal degradation of combustor components. Additionally, hot spots can occur within the combustor. Hot spots or thermal gradients can cause significant thermal stresses in the combustion liner as common materials expand when heated.
With some of these concerns in mind, a combustor with improved thermal resistance and with a reduced temperature gradient would be welcome in the art.